High Density Stacking Capability Drives Productivity in End-Use 3D Part Production at Decathlon

Product: Figure 4
Industry: Consumer Products and Retail

Decathlon, the world’s largest sporting goods retailer, is using the high-speed Figure 4 platform and new stacking feature of 3D Systems’ 3D Sprint® software to enable direct production of 3D printed end-use parts. The stacking feature enables batch production of one or multiple parts through a combination of user-defined and automated tools, and removes significant time from the print preparation process.

“By stacking parts we are able to print in batches of 100, and have reduced the time it takes to prepare a build from 30-60 minutes to just 6-10 minutes. The combination of stacking and production-grade materials makes Figure 4 ready for production.”

– Gregoire Mercusot, Materials Engineer, ADDLAB, Decathlon

The Challenge

VALIDATE EFFICIENT PRODUCTION WITH ADDITIVE MANUFACTURING

Componente para gafas de Decathlon diseñado para conectar la lente al marco

When faced with a mold injection problem on a small component for shooting glasses that connects the frame to the lenses, Decathlon opted to test the new 3D stacking solution developed by 3D Systems to evaluate additive manufacturing for production. After conducting a feasibility study on the Figure 4 solution and stacking feature, Decathlon’s teams confirmed the productivity and economics of additive manufacturing and decided that this solution could be considered for batch-run production of the final product.

The Solution

01 Part Stacking Feature in 3D Sprint Software

Captura de pantalla del software 3D Sprint que demuestra la función de puntal para la fabricación apilada

Decathlon’s additive manufacturing lab (ADDLAB) uses 3D Systems’ Figure 4 3D printing solution across a range of applications (including mold master patterns), and is now considering using the new high density part stacking capability of 3D Systems’ 3D Sprint software to facilitate direct production. 3D Sprint is an advanced, all-in-one software that streamlines the file-to-pattern workflow with tools for print file preparation and optimization, including automatic support generation, and optimized part placement to maximize productivity. The new stacking feature helps users print high volume batches with an efficient file preparation workflow.

To use the stacking feature, users import a part and base file, define the stack in terms of orientation and part quantities, and use automated tools to replicate consecutive vertical stack layers and supports. According to Decathlon engineer Gregoire Mercusot, stacking has reduced print preparation time by as much as 80%. Builds that used to take 30 minutes to an hour to prepare can now be completed in six to 10 minutes.

Mercusot says the utility of this function goes well beyond production: “I use this feature several times a week whenever I need multiple parts. It’s incredible for production, but it’s also very useful for prototyping,” he says.

02 Production-Grade Materials

Decathlon is using the Figure 4® PRO-BLK 10 material for this functional eyeglass component, citing the material’s strong rigid properties and fast print speeds (62 mm/hr) as key benefits. This high precision material produces parts with smooth surface finish and sidewall quality, and has excellent long-term mechanical properties and environmental stability, bringing a new level of assurance to 3D production. From its production feasibility study, Decathlon confirmed reproducibility across print batches and full functionality of the part.

03 Print Speed

Placa de impresión llena de piezas impresas en 3D apiladas de Figure 4

Figure 4 is a projection-based additive manufacturing technology that uses a non-contact membrane to combine accuracy and amazing detail fidelity with ultra-fast print speeds. Decathlon uses the Figure 4 Modular system to print stacks of 100 parts in 85 minutes, which is equivalent to just 42 seconds per part. The Figure 4 Modular is a scalable, semi-automated 3D production solution comprised of a central controller that can be paired with a single printer-module up to 24 printer modules, making it a flexible option that poises businesses for growth.

04 Post-Processing

The high-density stacking capability of Figure 4 brings efficiencies of scale to post-processing as well as part building, allowing Decathlon to treat a batch of parts the same as a single part. This means that the time it would take for Decathlon to clean, cure, and remove the supports from a single part remains the same, even for a batch of 100 parts. For Decathlon’s safety glass application, it takes six minutes to clean all 100 parts, 90 minutes of hands-free time to cure them, and ten minutes to remove supports from the entire batch.

Valiant TMS shows benefits of Siemens and Realtime Robotics partnership

Product: Tecnomatix
Industry: Automotive and Transportation

Recent proof of concept with a global automotive line builder shows significant savings in the engineering time required to program multi-robot systems.

Valiant TMS participated in a proof of concept with Siemens Digital Industries Software and Realtime Robotics (RTR) which showed that RTR’s technology seamlessly integrated into Tecnomatix Process Simulate software simplifies robot programming and interlocking by automating motion planning. The combined technology enables manufacturers and integrators to easily program, simulate and validate multi-robot systems, significantly reducing engineering time.

For the proof of concept, TMS provided a recent engineering study for an automotive body construction framing station. TMS provided KPIs like the required cycle time and the required time it takes today to program the robots. In this case, it takes 90 hours of programming for the 7 robots selected to produce the 60 weld spots required. Framing station fixtures and robot end-of-arm tooling is complex and the robots need to work in a very tight space.

“The combination of Process Simulate with Realtime Robotics improves our efficiency, reducing our offline programming efforts by more than 80%.”

It took only 15 hours to create the required robot roadmaps and to demonstrate collision-free robot motions and on-the-fly interlocking to TMS while achieving the required cycle time. This shows a reduction in programming effort of more than 80% in comparison to the typical required engineering time.

“The combination of Process Simulate with Realtime Robotics’ automated motion planning and interlocking has provided a significant improvement to our efficiency, reducing our offline programming efforts by more than 80%”, says Michael Schaubmayr, Group Manager Mechanical Engineering Simulation, TMS Turnkey Manufacturing Solutions GmbH. “This presents to us a tangible and strategic advantage in the industry.”

Additional optimizations can be achieved by trying different design options since reprogramming the robots to test an alternative is almost cost-free. All that is required is to set the target points for the robots in Process Simulate and, while running the simulation, allow the Realtime Robotics controller to automatically calculate the required motions and interlocks.

Watch this video to see the solution in action:

Cummins Uses Geomagic Software and Metal 3D Printing to Get 1952 Race Car Running Again 50% Faster

Product: Geomagic Design X/Control X
Industry: Automotive

The #28 Cummins Diesel Special shocked the racing world in 1952 when it captured the pole position at the Indianapolis 500 (Indy 500) with the fastest lap time in history. This feat, along with the car’s many other innovations, won it a prominent place in racing history.

Sixty five years later, #28 was invited to the Goodwood Festival of Speed in the United Kingdom to participate in the legendary Goodwood Hillclimb along with hundreds of modern and heritage cars. While preparing #28, the Cummins engineers discovered that the water pump was so corroded it would probably not survive the event. If the #28 car was to make it to Goodwood in working order, it needed a new water pump.

The original water pump was a unique design specific to the #28 car, which meant no spare production parts would fit the bill. To complicate matters further, they had to ship #28 within a matter of weeks, which ruled out traditional sand-casting methods as infeasible for a replacement part given an estimated lead time of 10 weeks. Instead, Cummins engineers turned to reverse engineering and metal additive manufacturing (AM) using a ProX DMP 320 metal 3D printer by 3D Systems with help from 3rd Dimension Industrial 3D Printing, a high-quality production metal manufacturer specializing in 3D direct metal printing (DMP). The new water pump was 3D printed in only three days and the entire process took five weeks instead of 10.

A Page Out of Racing History

#28 was the first Indy 500 car equipped with a turbocharger and the first whose aerodynamics were optimized in a wind tunnel. It ran its four qualifying laps at a record-breaking average speed of 138.010 mph.

Since its momentous run in 1952, #28 has been displayed at the Indianapolis Motor Speedway Museum and the Cummins corporate office building. In 1969, #28 ran a lap around the Indy track prior to the start of the race to mark the Cummins 50th anniversary celebration. The last time #28 ran was at the Goodwood Festival of Speed in the late 1990s.

“As we prepared the car to run again for the first time in almost 20 years, we noticed severe pitting and corrosion on the water pump,” said Greg Haines, design and development leader for the X15 engine and member of the Cummins history and restoration team. “In a few places, the housing was pitted all the way through and was only kept from leaking by mineral deposits that covered the holes. We needed a new housing quickly if we were to meet our commitment to run the car at Goodwood.”

Racing to Produce a New Water Pump

The baseline method for building a new pump housing is the same method that it used to build the original pump: machining a plastic or wood pattern and using it to form a sand mold for casting. Using this method, it would have taken about 10 weeks to build a single housing, ruling out a run at Goodwood. The lead time for the new water pump housing could have been reduced by 3D printing the new casting pattern or even 3D printing the sand casting mold itself, but the greatest productivity gains available came from bypassing the casting process altogether and using reverse engineering and 3D printing to produce the final part directly in only five weeks—50 percent faster.

Scanning

Cummins engineers began by scanning the existing water pump housing with a CT scanner. They selected a CT scanner because the pump contained many undercuts and other internal geometries that would have been impossible to capture with a laser scanner or other line-of-sight imaging tool.

Inspecting

To verify that the scan data was accurate before moving forward, the engineers imported the point cloud data generated by the CT scanner into Geomagic Control X inspection and metrology software where they separated and aligned the internal and external geometry of the pump.

“For a project like this, we typically separate out the internal volute geometry from the body so we can model it as a core and do a comparison back to the point cloud data to be sure all our work is accurate,” said Chris George, master CAD model team leader for advanced system design for Cummins.

Reverse Engineering

With good scan geometry to jump-start its design work, Cummins used Geomagic Design X reverse engineering software to convert the point cloud to a nonparametric solid model to perform CAD fit checks. These checks helped the Cummins team determine the right assembly dimensions for the impeller and shaft and how everything would ultimately fit and seal together.

According to George, Cummins uses Geomagic Control X and Geomagic Design X as its primary software for point cloud manipulation. “The 3D Systems Geomagic software provides a complete solution for processing and inspecting scan data and converting it to a solid model,” he says. “We use them for every reverse engineering project we do, which often requires geometric reconciliations, finite element analyses of structure and flow, and model-to-scan comparisons reported to our engineering customers.”

“The 3D Systems Geomagic software provides a complete solution for processing and inspecting scan data and converting it to a solid model. We use them for every reverse engineering project we do.”

—Chris George, Master CAD Model Team Leader for Advanced System Design, Cummins

Designing

Due to the significant corrosion of the original part, Cummins could not use the model created from the scanned data as the basis for 3D printing. Instead, Cummins engineers imported the nonparametric model into PTC Creo® 3D CAD software to act as a template for creating a parametric model. In light of the physical damage to the scanned pump, the Cummins team had to make informed decisions as they 3D modeled the replacement to achieve a functional final model.

3D Printing

They then sent this file to the team at 3rd Dimension, who cleaned it up, analyzed it for optimal print orientation, and assigned supports for stable printing. 3rd Dimension engineers further sliced and hatched the part to define the movement of the laser during the build.

Although the original water pump housing had been made of magnesium to help reduce weight, magnesium’s susceptibility to corrosion following extended water and coolant exposure was a large factor in the problem Cummins was trying to solve. Therefore, 3rd Dimension manufactured the final 3D-printed part using LaserForm 316-L stainless steel material on a ProX DMP 320 metal 3D printer.

“The larger build volume of the ProX DMP 320 enabled us to have some additional options with part orientation, which helped us optimize supports, and the print speed allowed us to get the print done in the time we had,” said Bob Markley, president of 3rd Dimension. “The ProX DMP 320 also does not use a binder to join the material, which means the output is a pure alloy that performs like real metal—because it is real metal. This is a benefit to final part performance given the operational environment.”

Only three days after receiving the 3D file of the water pump geometry, 3rd Dimension sent Cummins the completed pump housing.

Making Racing History Again

The housing mated perfectly with the other pump components and provided like-new performance for over six Goodwood Hillclimb runs. Just as it had at Indy, #28 thrilled the fans at Goodwood and was featured in “The 10 Best Things We Saw at the 2017 Goodwood Festival of Speed” by Car and Driver magazine.

In addition, as it did for the Cummins 50th anniversary in 1969, the #28 had a featured role in celebrating the Cummins 100th anniversary by running a parade lap around the track prior to the start of the 2019 Indy 500 race.

Siemens solutions assist in the design of an innovative marine stabilizer system

Product: NX CAD
Industry: Consumer Products and Retail

Siemens Digital Industry Software solutions help marine manufacturer reduce testing time by up to 20 percent

Stability at sea

If there’s anything that can spoil a relaxing trip on the water, it’s an unstable boat. Choppy surf can cause significant damage to personal belongings as well as the boat. Whether you’re fishing, scuba diving or just out on the water, ship stability is an essential part of safe sea travel. As a result, ship stabilizers are valuable commodities. Any experienced sailor understands the importance of marine stability in ensuring a sound trip at sea; however, not every stabilizer system is perfect. In fact, a common issue with conventional fin-driven stabilizers is insufficient roll dampening at lower speeds and protruding fins. This issue has hampered the consumer experience. Stability is necessary at low speeds, and protruding fins can become damaged in shallow waters. The last thing your customer wants is to be out at sea when their new stabilizer fails. Considering consumers have a low tolerance for product failure, one bad experience may be all it takes for consumers to jump ship from your product. Only the stabilizer manufacturers who deliver consistent quality survive.

Realizing opportunity

Located in ‘s-Hertogenbosch, Netherlands, DMS Holland is an international specialist in the field of motion control on yachts of up to 30 meters. DMS Holland’s goal is to reduce the roll movement of yachts to improve onboard comfort, reduce sea sick-ness and improve safety. The speed in which DMS Holland’s marine stabilizer systems achieve stabilization differentiate themselves in the market. Their stabilizer systems are based on the Magnus effect, a phenomenon in which a rotating cylinder works away from its principal paths of motion to achieve stability. Where a traditional stabilizer requires a yacht to be traveling at a considerable speed, their product achieves stabilization at just 3 to 12 knots. This differs from conventional fin-based systems due to its small design and greater roll dampening abilities at lower speeds. Brabant Engineering, a mechanical engineering company in Best, Netherlands, is responsible for the design and development of DMS Holland’s Magnus Master, the newest generation of rotor stabilizing technology which features retractable rotors that eliminate the risk of damage. The company is providing DMS Holland with their design expertise to develop the forward-thinking product they envisioned.

“DMS Holland wanted to provide the highest level of stability, comfort, and safety onboard. Overall, we wanted to make life at sea much more comfortable and easy,” says Patrick Noor, sales and marketing director, DMS Holland. “To realize our vision, we need quality companies such as Brabant Engineering to assist us with the mechanical engineering for our stabilizers.”

Sailing toward solutions

Brabant Engineering utilizes the innovative design applications found in Siemens Simcenter™ 3D to accurately design and simulate its projects.

“All the material properties are embedded into the software design, and Simcenter 3D helps us analyze the behavior and durability of our product,” says Bertie Tilmans, lead engineer, Brabant Engineering. “By providing accurate material properties and seamless integration of multiple design alternatives, we can save valuable time during product development.”

Brabant Engineering used Simcenter 3D to accurately simulate the Magnus effect and confirm the Magnus Master could handle 1,100 revolutions per minute. “I have been using Simcenter 3D for the last seven years and I am very fond of the versatility of the software,” says Tilmans. “This versatility allows companies to predict the behavior of different aspects of a product’s design to find the most effective solution.”

Reducing development costs and prototyping cycles

By properly utilizing computer-aided design (CAD) software – such as with their use of Siemens NX™ software – Brabant Engineering uses the powerful and flexible capabilities of NX CAD to drastically reduce the cost and time it takes to design such innovative products. The combination of NX CAD for design and Simcenter 3D for performance prediction help to accelerate product-to-market more efficiently.

Depending on the size of the device, physical prototypes can cost exponentially more than the price of the product. Simulations can save significant time and costs in the early stages of a project. Using Simcenter 3D, instead of relying on a costly physical prototype, Brabant Engineering saved approximately 10 to 20 percent of total testing and qualification time. They were able to shorten the test cycle and receive direct results.

Rikkert Gerits, project leader, Brabant Engineering, confirmed that using Simcenter 3D dramatically reduced the amount of physical prototyping necessary.

“Using 3D simulation tools, we don’t have to build an actual prototype, which saves us considerable time and money,” says Gerits. “We use several Siemens products, like Simcenter, NX CAD, and Teamcenter, and they’re delivered by cards PLM Solutions, a Siemens Digital Industries Software solution partner. We contact them with any specific question we have regarding the software.”

CAD systems offer users the ability to easily interchange various product components. CAD and computer-aided engineering (CAE) systems also provide the necessary tools to rapidly re-engineer and explore the performance of new designs. Gerits explained how these simulation systems also allow for a speedy virtual-proto-typing phase. By simulating the product in real time, users can more accurately predict product durability under certain conditions. This provides companies with significant cost and time savings when compared with designing, producing, testing and recording data of a physical prototype. Brabant Engineering estimates a 10 to 15 percent total cost savings by using simulation to prevent flaws compared to what it would cost to fix/repair those flaws.

Establishing a strong relationship

Sjef van de Laak, managing director, Brabant Engineering, says Siemens solutions are key in the company’s engineering design process. “Siemens is the supplier of the software we use, and the importance of cards PLM Solutions is they know the software very well and support our simulation needs,” he says. Product development would be disrupted without this open line of communication. As such, cards PLM Solutions and Brabant Engineering maintain a constant dialogue.

Sharing the Magnus Master worldwide

The Magnus Master is already receiving considerable attention. Since its introduction in 2015, the Magnus Master has developed a reputation of quality throughout the Netherlands and helped make DMS Holland a global business.

This combined effort between Brabant Engineering, DMS Holland, and Siemens is a perfect example of how cooperation can lead to groundbreaking innovation.

Electrolux implements worldwide 3D factory and material flow planning

Product: Tecnomatix
Industry: Consumer Products and Retail

With Tecnomatix and Teamcenter, Electrolux creates uniform, efficient manufacturing processes and systems

Globally distributed production facilities

Electrolux AB, based in Stockholm, Sweden, sells appliances for household and commercial use in 150 countries around the world. With around 58,000 employees and 46 pro-duction sites, the company develops and manufactures products of numerous brands: in addition to Electrolux, the top brands Grand Cuisine, AEG, Zanussi, Frigidaire and Westinghouse enjoy a particularly high reputation. In 1996, the German AEG brand was acquired from Daimler Benz, together with several divisions and locations of the group. This is how the factory in Rothenburg ob der Tauber, founded in 1964, came to Electrolux, which today produces 600,000 stoves and 1,400,000 cooking ranges per year for the European market. “We attach great importance to implementing in detail the essential product characteristics of each brand in development and production,” reports Bernd Ebert, director of Global Manufacturing Engineering − Food Preparation at Electrolux. Based in Rothenburg, Ebert ensures that all Electrolux cooking appliance factories implement uniform processes and systems.

High priority for virtual factory planning

As part of a comprehensive digitalization strategy covering all areas, 11 digital manufacturing projects are on the agenda of the Swedish global corporation. Ebert has assumed responsibility for two global projects with the highest priority. They aim to create “digital twins” of all manufacturing sites: In the virtual manufacturing project, an advanced planning tool was selected and introduced for early design verification to develop products that are production- and assembly-friendly. For example, assembly sequences and movements will be planned and optimized three-dimensionally to pre-vent collisions. The prerequisite for this is the development of three-dimensional fac-tory layouts, which is the focus of the second project, 3D factory layout. The layouts will be created using a standard factory planning tool that can simulate both the plant and the material flow on the basis of 2D data in order to optimize capacity and efficiency.

Global platform for digital manufacturing

Software selection began in 2010, when only a few had powerful software for 3D factory planning. A small, specialist team led by Ebert worked closely with the company’s IT department in Stockholm. Starting in 2012, Teamcenter from Siemens Digital Industries Software was deployed there as a strategically important product development platform for product lifecycle management (PLM) at Electrolux. Discussions about Siemens’ future strategy led to an offer to test a pre-release version of the 3D layout software Line Designer in an early adopter program.

Siemens was given the opportunity to use original data to build a showcase demonstrating the performance of the software on real problems. As a result, in 2016 Line Designer was selected in conjunction with solutions in the Tecnomatix® portfolio, including the Process Simulate solution. The main reasons for this decision were the advantages of a tight Teamcenter integration of these solutions: “We can save all resources created with Line Designer as libraries in Teamcenter, manage them and make them available to all users worldwide,” explains Ebert. “This way we preserve an entire infrastructure of software and hard-ware including training material and can build on the existing users ́ experience with Teamcenter.” The expected results were a close alliance for product development and a global, common platform for factory planning and material flow optimization.

Roll-out strategy after pilot project

In a pilot project carried out in Rothenburg in 2016, employees received training by Siemens and developed, among other things, a new assembly line and automated housing assembly with Line Designer. Ergonomics studies were carried out with Process Simulate and cycle times were successfully optimized using simulations. “The Tecnomatix and Teamcenter solutions have proven themselves in the best way,” reports Ebert as project manager. “At the same time, we have gained valuable experience for a worldwide deployment.” The core team has now trained specialists for each of the three software solutions, who can provide advice and support to the decentralized employees at the locations. The system areas created with Line Designer, such as conveyors and lifts, or models of material transport trolleys and other devices, can be parameterized. “By making the 3D models and scenarios avail-able worldwide, we save lots of work,” reports Ebert. “After adjusting the parameters, they are simply re-used elsewhere. This brings us almost automatically closer to the desired standardization of processes and systems across the product lines − cooking, washing and dishwashing, drying and cooling/freezing − as well as the sectors USA, South America, Asia/Pacific and Europe.” “Based on the experience gained from the pilot project, the worldwide rollout has now been carried out in waves, each of which includes the intensive training and familiarization of the employees at one location,” says Ebert. “In order to secure our major projects, we initially selected four locations with high investment volumes.”

Project Anderson, South Carolina

One location involves the complete construction of a new refrigerator factory in Anderson, South Carolina, in which refrigerator production is to be concentrated on the American continent by mid-2019. There, a higher degree of automation should save around 30 percent of human labor. Many processes were planned with Tecnomatix in order to develop a new automation concept, to plan the factory correctly at the first attempt and to secure the immense investment.

A very time-consuming production area is the plant for foaming the refrigerator walls with hardening. All areas before and after are based on the process times there. In order to design this bottleneck correctly at the first attempt, the process was mapped and simulated as a one-piece flow. “A lot of details had to be taken into account, such as different materials and different models,” says Ebert. “To depict all this was very time-consuming, but it was worth it.” The accurate results of Plant Simulation eliminate the need for large buffers, saving approximately $2,000,000 by having one conveyor and one high-bay warehouse for 5,000 refrigerators. After foaming, the assembly processes branch to four lines. Here, the train routes of the material flows were planned, simulated and optimized with all purchased parts of the parts lists for 30 models of the modular product design that go from the truck to the assembly lines. “An employee of Siemens has laid the foundations for the train routes. But in the meantime, our mate-rial flow is improved daily by our own employee − we have already achieved our effectiveness targets,” reports Ebert.

With Process Simulate, the employees also planned robot cells that would take over some of the previously manual processes. “Even if the cells are not yet completely detailed, we can decide with a high degree of certainty whether we need one or three robots,” says Ebert. The high planning reliability is conveyed to the management in 3D scenarios and videos.

“A big investment requires a lot of persuasiveness,” Ebert asserts. “With the good visualization possibilities of Tecnomatix, I can show the management an early stage of planning that makes the processes plausible. The 3D technology helps with the verification of assembly concepts as well as with the selection of suppliers for automation solutions and provides insights that I didn’t have before.”

Worldwide deployment concept

The first projects have proved that Tecnomatix and Teamcenter tools can be used to solve tasks and achieve goals. However, the employees deal with the powerful tools regularly. “We need specialists to take on new roles in our global team,” Ebert says. “For successful standardization, every topic must be described centrally.” Further major projects are now also pending in Europe. “The factory is too expensive to use as an experimental field,” Ebert says, referring to Professor Dr. Hans-Jürgen Warnecke, a well-known scientist and former president of the Fraunhofer Gesellschaft in Germany. “To test new concepts, there are efficient simulation tools that make production downtime superfluous.”

Miele: A better way to make medical instruments come clean

Product: Simcenter
Industry: Medical and Forensic

A world leader in premium domestic products

Founded in 1899, Miele is a world leader in premium domestic products such as cooking, baking and steam-cooking appliances, refrigeration products, coffee makers, dishwashers, laundry and floor care products. Miele also produces specialized dishwashers, washer-extractors and tumble dryers for commercial use as well as washer-disinfectors and sterilizers used in medical and laboratory settings.

In its efforts to continuously improve its product lines, the company was particularly interested in improving the development of its washer-disinfector machines. “The major development challenge with washer-disinfector machines is the variety of items that need to be cleaned,” says Tobias Malec, development engineer at Miele. “Each piece of every medical instrument has different cleaning requirements. Some things only need cleaning on the surface. Other items, such as hollow instruments, need to be cleaned both inside and out. Different water pressures are needed in each case.”

Working with special racks

Due to these requirements, a special rack is tailored to every item that needs cleaning to enable the best possible handling and hydraulic performance. Each rack secures the items being cleaned, and includes the hydraulic connections between the circulating pump and the nozzles through which water sprays. The variety of racks makes it difficult to harmonize the entire production system.

It is essential to adapt the frequently changing hydraulic conditions of the rack, and to understand the cleaning pressure required during the operating state inside each rack. The cleaning pressure results from the intersection point of the hydraulic resistance curve of the rack and the characteristic of the circulating pump.

For this engineering challenge, Miele uses Simcenter Amesim™ software, a mechatronic system simulation solution part of the Simcenter portfolio from Siemens Digital Industries Software. This solution helps Miele engineers simulate the operational characteristics of new products early in the design stage, revealing ways to improve functionality while reducing the need for physical prototypes. “Using Simcenter Amesim enables us to model the racks as super components, with the circulating pump operating as a characteristic and the washing machine itself as a system boundary,” says Malec. “Thanks to the system simulation, we can evaluate future operating points by changing the geometries of the cleaning nozzle or the water lines.”

He notes, “Using this software, we are now much more effective in the predevelopment phase. Before, without the support of Simcenter Amesim, we had to build a real prototype of the washing machine and perform multiple pressure measurements. Afterwards, based on the pressure results, we needed several redesign loops in the prototype phase to reach the required specifications. This was very time-consuming and costly.”

A typical model prepared using Simcenter Amesim includes hydraulic and hydraulic-resistance components. The machine is modeled, including its water lines and the circulating pump. The water lines include back-pressure valves and a coupling with the rack models. Some nonstandard valves have been customized and are represented by generic elements, such as orifices or T-junctions, which are validated by internal measurements.

A cleaning rack consists of a network of jets and pipelines connected with two coupling points of the machine. To ensure that compatibility and clarity are quickly achieved, the rack is integrated into the model as a supercomponent and is represented with an icon.

Mechatronic system simulation is the key

The various pumping rotation speeds are then tested virtually. This allows Miele to investigate the pressure evolution on pre-defined sensor positions to validate the simulation model. The machine operating state is quasi-static, so dynamic examinations are negligible for those types of investigations. The simulated pressure values provide the basis to make adjustments in rack design.

“System simulation enables us to easily study the impact and interactions of crosssection changes,” says Malec. “Changeovers can be optimized or nozzle parameters varied to achieve a more constant pressure distribution. Constant pressure distribution enables good cleaning capacity in all parts of the machine.”

The design exploration capability also helps establish consistency for the spray arms. By setting targeted boundary conditions and defining degrees of freedom (DOF), the optimal nozzle configuration can be found quickly using Simcenter Amesim. “System simulation is an extension of the common 3D computational fluid dynamics (CFD) simulation on a subsystem level,” says Malec. “Correlations become clear very rapidly. Without system simulation, these correlations can only be realized using measurements on expensive prototypes.”

Malec concludes, “The longevity and high quality of our products address the sustainability issue. Our customers don’t have to buy a new machine every few years, but can rely on our consistent quality. That doesn’t just save money, it is also good for the environment. We are also reducing our consumption of resources and using ecologically sound materials for production.”